acos()  Math  class methodS2C Home  « Globals « Math « acos()


Returns the arccosine of a number in radians.

  • Radians to Degrees - divide number by (Math.PI / 180).
  • Degrees to Radians - multiply number by (Math.PI * 180).
  • Like all class methods acos() should be used on the class rather than an instance of the class.


Signature Description
Math.acos(value)Returns the arccosine of a number in radians.


Parameter Description
valueThe number you wish to find the arccosine in radians for:
  • A number in the range -1 to 1.
  • Values outside this range return NaN.


The code below displays acos() usage.

 * Store results in an array.
var acosValues = new Array(5);
acosValues[0] = Math.acos(-1);
acosValues[1] = Math.acos(0);
acosValues[2] = Math.acos(0.75);
acosValues[3] = Math.acos(-2);
acosValues[4] = Math.acos('a string');
acosValues[5] = Math.acos();

Press the button below to action the above code:

Related Tutorials

JavaScript Advanced Tutorials - Lesson 4 - Math

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